Grease gun or the like



Jan. 17, 1967 F. L. ANDERSON 4 3,298,574

GREASE GUN OR THE LIKE Filed June 6, 1966 2 Sheets-Sheet 1 I Franc/J Z Ana exam INVENTOR.

ATTORNEY Jan. 17, 1967 F. ANDERSON 3,298,574

GREASE GUN OR THE LIKE Filed June 6, 1966 2 Sheets-$heet 2 7 3 aid-M7 /m f fa/i CIJ A flaw/"J00 INVENTOR.

United States Patent 98,574 GREASE GUN OR THE LIKE Francis L. Anderson, Houston, Tex., asstgnor to William E. Hamm, Houston, Tex. Filed June 6, 1966, Ser. No. 555,453 6 Claims. (Cl. 222-262) This application is a continuation-in-part of a previously filed application of the same inventor, Serial Number 427,902, filed January 25, 1965, now Patent 3,265,252.

This invention relates to pressure fluid operated mechanism for dispensing fluid materials and more particularly to apparatus for dispensing heavy grease or similar semi-solid materials under high pressure.

The invention is capable of use for the dispensing of a wide variety of liquid and semi-solid fluid materials under pressure and finds particular utility .in connection with the dispensing of relatively viscous, semi-solid materials, such as heavy grease or other substances which can be made to flow only by the use of relatively high pressures and which may be conveniently furnished in the form of sticks or other similarly shaped bodies for use in high pressure dispensing apparatus.

In the dispensing of various kinds of heavy fluid materials, such as lubricating oils and greases, caulking compounds, plastic sealants and the like, it is common to make use of dispensing apparatus of the grease-gun type adapted to be operated by air pressure. Such apparatus is usually designed for operation by the ordinary compressed air sources available in shops, service. stations and other places having compressed air equipment capable of delivering pressures of about eighty to one hundred pounds per square inch, the material being delivered to lubricant fittings or the like by means of pressure operated plunger mechanism of small capacity whereby high pressure may be applied to the material. In apparatus of this kind the material is customarily fed to the plunger-mechanism by means which operates under substantially the same pressure as the plunger mechanism, and which does not lend'itself satisfactorily to the dispensing'of relatively heavy materials such as hard greases or the like.-

The present'invention has for an important object the provision of pressure fluid operated dispensing apparatus which is designed for dispensing at high pressure heavy, semi-solid, fluid materials, such as hard grease, and which may be satisfactorily operated under the 'pressureavailable from sources ordinarily in use.

Another object of the invention is to provide fluid dispensing apparatus having dispensing mechanism which is operated by the pressure of fluid from a source of fluid under pressure and means for, feeding the fluid to be dispensed to such mechanism at a pressure higher than the pressure from said source.

A further object of the invention is the provision in fluid dispensing apparatus having dispensing mechanism which is operated by the pressure of fluid from a source of fluid under pressure and means for feeding the fluid to be dispensed to such apparatus under pressure, of means operated by pressure from said source for applying to said material to be fed a pressure higher than the pressure of said source.

Another object of the invention is to provide fluid dispensing apparatus having dispensing mechanism and means for feeding material to be dispensed to such mechanism, said means and mechanism being operable by fluid pressure from a common source of fluid under pressure and including means for supplying fluid from said source for the operation of said feeding means at a higher pressure than the pressure of said source.

3,298,574 Patented Jan. 17, 1957 ice A' further object of the invention is the provision of dispensing mechanism for heavy fluid material, such as hard grease, or the like, which is operable 'byfluid under pressure and wherein the supply of the material to be dispensed may be easily and quickly replenished.

Another object of the' invention is to provide fluid dispensing apparatus of the type referred to having a main operating piston which reciprocates in a main cylinder and embodying improved valve'operat'ing mechanism by which a pressure fluid is directed first into one end of the main cylinder whilefiuid is exhausted from the other end thereof and then into the other end of the main piston while fluid' is exhausted from said one end thereof. v

The above and other obvious objects and advantages of the invention may best be understood from the following detailed description constituting a specification of the invention, when considered in conjunction with the annexed drawings, whereinr FIGURE 1 is a central, longitudinal, cross-sectional view of a preferred embodiment of the invention showing the same with the parts in the positions which they occupy prior to a dispensing operation of the apparatus;

FIGURE 2'is a fragmentary cross-sectional view taken along the line 22 of FIGURE 1, looking in the direction indicated by the arrows;

FIGURE 3 is a cross-sectional view on a somewhat enlarged scale, taken along the line 3-3 of FIGURE 1, looking in the direction indicated by the arrows;

FIGURE 4 is a cross-sectional view taken along the line 44 of FIGURE 3, looking in the direction indicated by the arrows;

FIGURE 5 is across-sectional view taken along the line 5-5 of FIGURE 4, looking in the direction indicated lubricant dispensing means, and a fluid pump operated;

in response to actuation of the piston of the power cylinder and which supplies fluid at a higher pressure than the pressure fluid supply sourceto a lubricant containing cylinder which supply'lubricant to the dispensing means The mechanism includes valve mechanism by which the supply and exhaust of pressure to the power cylinder is controlled in response to movements of the power piston to reciprocate the piston.

Referring now to the drawings in greater detail the dispensing mechanism of the invention, as shown in the present illustration, has adispensing and compressor barrel, generally designated 10,'and a supply cylinder 12,

which are connected together at one end by a fitting 14 to form a 'unitary structure or gun, of which the parts are threada'bly-connected to permit ready disassembly. The barrel 10, is preferably made up of threadably connected sections 16, 18 and 20, respectively, of which the section 16 may be called the dispenser section, the section 18 beinga valve section and the section 20 being a compressor section.

The fitting 14 may conveniently be formed'as a casting having a material feeding chamber 22, provided with" an inlet opening, Which is internally threaded, as shown at 24 for the threadable connection thereto of the supply cylinder 12,'the chamber being also incommunication with a longitudinal dispensing bore 26formedin'the' casting. The fitting has an externally, threaded boss28...

to which one end of the barrel section 16 is threadably connected, the bore 26 being centrally located relative to the boss. A dispenser actuating chamber 30-is formed within the section 16, which section is externally threaded at its other end, as shown at 32 for threadable connection to the internally threaded end of the section 18. A

valve chamber 33 is formed within the section 18. The

section 18 is in turn externally threaded at itsother end, as seen at 34, for connection to the internally threaded end of the compressor section 20, within which a compression chamber 36 is located. 7 i

A piston rod extends through the chambers 30, 33 and 36 of the barrel, which rod carries a dispensing piston 38 in the dispenser actuating chamber 30, and a compressor piston 40 in the compressor chamber 36. The piston rod also has at one end a dispensing plunger por 4 chamber 33, the opening 84.,being closed by the block 48 when the valve is in position to admit pressure through opening 86 into passageway 55 through port 57, and the opening 86 being closed by the block 48 when the valve is in position to admit pressure from chamber 33 into passageway 52 through opening 84.

The valve block 48 has an elongated slot 88 in which a slide member 90 is slidably disposed, which has a portion 92 which is engageable with the valve element 50 in the slot 80 thereof to turn the element in response to sliding movement of the slide member in slot 88. The .slidemember 00 is yieldingly held against longitudinal movement in the valve chamber 33 by coil springs 94 and tion 42, slidably extended into the bore 26 and at the other end a plunger portion 44 which works in a bore 46 in the section which is open at its outer end. Within the chamber 33, the piston rod carries a valve block 48, upon which a valve element 50 is rotatably mounted on a pivot bolt 51, best seen in FIGURE'4. As best shown in FIGURES 4 and 5, the valve block 48 is formed with a passageway 52 which is in communication through a port 53 with the interior of the chamber 33 and with the interior of an outer pipe 54, forming a part of the piston rod and which is connected at one end to the block 48 and at its other end to the piston 38, and the valve block also has a passageway 55 in communication through a port 57 with the interior of chamber 33 and with the interior of an inner pipe 56 also connected at one end to the block and at its other end to the piston 38.

Outer pipe 54 has an opening 58 adjacent the piston 38, which opens into the chamber on one side of the piston 38, and inner pipe 56 is open at its outer end into chamber 30 on the other side of piston 38, through openings 60 in a hollow extension 62 attached to the piston and whose interior is in communication'with the inner pipe and the interior of chamber 30.

The valve block 48 has a further passageway 64 which opens to the exterioro-f the block through a port 65, the passageway 64 being in communication with the interior of a pipe 66 forming a part of the piston rod connected at one end to the block 48 and at its other end to the piston 40 in compressor chamber 36. Pipe 66 is in communication with the plunger 44 which is tubular and which opens to the exterior of the barrel through the bore 46. Y 8

Suitable packing, such as that indicated at 70 is 'pro-' vided between the outer pipe- 54 and the section 16, through which the piston rod is slidable and which forms a seal between the chambers 30 and 33. Similar packing, shown at 72 is provided about the plunger 42 in the bore 26 to prevent leakage into and out of the chamber 30, and packing means, such as that shown at 74, is provided about the plunger 44, in the bore 46, to prevent leakage from chamber 36 to the exterior.

The valve 50 takes the form of a fiat, plate like element having a fiat face which lies against one face of the valve block and is rotatable on the bolt 51 threadably secured to the block. The block 48 carries a bracket 76, through which the bolt 51 extends, and a'coil spring 78 surrounds the bolt beneath the bracket and bears against the valve element to hold the same tightly in contactwith the valve block. The element 50 is formed with an end slot 80, and is also provided with an'arcuate slot 82 in its inner face forming with the valve block a-valve passageway on port which moves with the element to one position to connect the port 57 with the exhaust port 65' and to another position in which the port '53 will be in communication with the exhaust port 65. The valve element 50 also formed with spaced apart openings 84 and 86, both of which are open to the interior'ofthe valve' 96, whose outer ends are seated in recesses 88 and 100 at the opposite ends of the valve chamber and whose inner ends bear against opposite sides of the slide member. The springs 94 and 96 are preferably of a type whose inner. ends are tapered, as by forming turns thereof of diminishing diameter toward the inner ends of the springs :as seen in FIGURE 7.

Means is provided for causing the valve member 50 to move from one of its extreme positions to the other with a snapping action, which means includes a latch member 102 movably mounted on the valve block 48 and which is urged by a coil spring 104 toward its latching position in engagement with the slide member to hold the slide member against sliding movement in the slot 88. The latch member 102 has a roller 106 which rolls on a trackway 108 mounted in the valve chamber and extending in thedirection of movement of the valve block. The trackway 108 has a central, depression 110 which terminates at each end in upwardly sloping ramp surfaces 112. By this arrangement the latch 102 will be in latching position to hold the slide member 90 against longitudinal movement relative to the valve block during that part of the movement of the block in which the roller 106 is in the depression, and when the valve block moves in either direction to cause the roller 106 to roll up either of the ramps 112, the latch will be released to' permit sudden longitudinal movement of the slide member in the slot 88 under the influence of one of the springs 94 and 96 to snap the valve 50 from one to the other of its positions. I

The trackway 108 is movably disposed in the valve chamber for longitudinal adjustment therein, as by means of a screw 114, whereby the exact positions of unlatching of the slide member 90 may be regulated.

In the operation of the mechanism, the spring 94 will be compressed upon movement of the valve block 48 to the left, as viewed in FIGURE 1 while the valve element 50 is held against movement in slot 88 by the latch102 until roller 106 moves upwardly along the left ramp 112 of trackway 108 to release the latch, whereupon the valve element 50 will be rotated with a snapping action into a position to cause the mechanism to be actuated to move the valve block to the right. As the valve block moves to the right the roller 106 again moves into depression to allow the latch to be relatched to hold slide member 90 against movement in slot 88 until the roller moves up the right ramp 112 of the trackway to release the latch, whereupon spring 96 will rotate the valve member with a snapping action back to a position to cause the mechanism to be actuated to again move the valve block to the left.

During the operation of the mechanism the spring94 will be allowed to suddenly extend when the valve element 50 snaps in one direction and the spring 396 will be suddenly extended upon snapping of the valve element in the other direction. Such extension of the springs with a snapping action has been found to result in breakage of the springs due to the fatigue caused by the rapid compression and extension action. Means is provided for preventing such breakage of the springs, such as that illustrated in detail in FIGURE 7, wherein the slide member 90 has an opening 116 therethrough which is substantially coincident with the axis of the springs 94 and 96 and through which a rod 118 is slidably extended into the springs. The rod 118 has at each end an eye 120 and is surrounded by coil springs 122 and 124 on each side of the slide member 90 whose inner ends bear against the smaller turns of the inner ends of the springs 94 and 96 and whose outer ends bear against the end eyes 120.

It will be apparent that by this arrangement the snapping action of the springs 94 and 96 will be checked or cushioned by the action of the springs 122 and 124 as the valve element 50 is rapidly snapped back and forth.

The compressor piston 40 has a passageway 126 therethrough and is provided with a check valve 127, which may be of the reed valve type to close the passageway 126 against the flow of fluid in one direction therethrough while allowing such flow in the other direction.

A passageway 128 is also provided in section 18 through which fluid may flow from chamber 33 into chamber 36.

The chamber 36 is in communication at its outer end with the end of the cylinder 12 remote from the fitting 14, as by means of a hose 130 connected at one end to a fitting 132 in communication with a passageway 134, through. which fluid may flow out of the chamber 36 through a check valve 136, but which prevents the backflow of fluid from the cylinder 12. The hose 130 is connected to cylinder 12 by a fitting 138 which is provided with a relief valve 140 which may be set to regulate the pressure supplied to the cylinder.

The cylinder 12 has a piston 142 movably disposed therein for movement toward the fitting 14 under the influence of pressure admitted to the cylinder through the hose 130 and which is provided with an extension or stop element 144 positioned for engagement with the wall of the supply chamber 22 to prevent the piston from moving from the cylinder into the chamber.

A handle 146 is provided for the barrel 10, which has a passageway 148 therein which communicates with any convenient source of fluid under pressure and which leads into the interior of the chamber 33 under the control of a valve 150 constructed to be opened by a trigger 152, to supply fluid under pressure to the chamber 33, and which is closed by a spring 154 to shut off the supply of such fluid from the chamber when the trigger is released.

At the discharging end of the equipment, the fitting 14 has a connection 156 leading to any desired location for the dispensing of the material, and which may be used to connect the equipment to any suitable grease fittings or other devices into which the materialis to be dispensed. A passageway 158 is also provided in communication with the bore 26 and leading to the exterior, which passageway is closed by a plug 160 which may be removed to allow the escape of air from the bore so that the bore may be completely filled with the material to be dispensed. A connection 162 is also provided through which fluid under pressure may be supplied to the chamber 22 under the control of an inwardly opening check valve 164 through a passageway 166, for a purpose to be explained hereinafter.

In making use of the dispensing apparatus, constructed as described above, the cylinder 12 may be unscrewed from the fitting 14 with the piston 142 located at the opposite end of the cylinder, and the cylinder filled with the material to be dispensed in advance of the piston. For this purpose the material to be dispensed may be supplied in the form of sticks shaped to fit the inside of the cylinder, or may be enclosed in a wrapper or the like for insertion therein. The cylinder may then be again screwed into the fitting and the passageway 148 of the handle 146 then connected in communication with the source of fluid under pressure, such as an air compressor.

With the apparatus thus loaded and the parts positioned as shown in FIGURE 1, the trigger 152 may be actuated to open valve 150 to supply fluid under pressure to chamber 33, the valve element 50 being in the position of FIGURE 3, to allow fluid from chamber 33 to flow through passageway-55 and inner pipe 56, through opening 60 into chamber 30 to move piston 38 to the left, as viewed in FIGURE 1, to retract the plunger 42 in the bore 26 to allow material from supply chamber 22 to enter bore 26. As the piston 38 moves to the left in chamber 30, fluid in advance of the piston may flow out of the same through the opening 58, outer pipe 54, passageway 52, groove 82 of valve 50, passageway 64 and pipe 66 to the exterior, thus exhausting the fluid from the chamber in advance of the piston.

When the piston 38 and the piston rod therewith, has moved to the limit of its movement to the left, the valve block 48 will have moved to a position to cause the latch 102 to be released, while the spring 94 will then be compressed to snap the slide member and the valve member 50 therewith to the right to position the valve to furnish pres-sure through outer pipe 54 to chamber 30 to the left of piston 38 and to exhaust fluid from chamber 30 through inner pipe 56 to move the piston 38 to the right, whereupon the valve mechanism will again be operated in the manner pointed out to reverse the motion of piston 38.

During the movement of piston 38 to the right in Chamber 30 fluid from chamber 33 will flow into chamber 36 through passageway 128 and through the passageway 126 of piston 40, and during the return or retracting movement of piston 38 the fluid in chamber 36 is prevented from flowing back through passageway 126 by the reed valve 127, so that fluid will be compressed in chamber 36 by movement of the piston 40 to the left therein to supply fluid to the cylinder 12 on the left side of piston 142 therein at a higher pressure than the fluid supplied to chamber 33 from the source. The compressor section 20 with its chamber 26 and piston 40, thus acts as a pump to supply fluid at a higher pressure than that supplied to chamber 33, which higher pressure is supplied to cylinder 12 to apply pressure to the material therein to feed the material to the bore 26 in advance of the plunger 42.

When the supply of material to be dispensed has been depleted from cylinder 12, the hose may be released from the fitting 138 and the supply line from the source of fluid under pressure disconnected from the handle 146 and connected to the connection 162 to supply fluid under pressure to chamber 22 to retract the piston 142 in cylinder 12, whereupon the cylinder may be unscrewed from fitting 14 and refilled with a new charge of the material.

The pistons 38, 40' and 142 will, of course, be provided with the usual seal forming elements, such as those shown at 170, 172 and 174, respectively, to prevent the flow of fluid past the pistons during operation of the apparatus.

It will thus be seen that the invention, constructed as described above, provides dispensing apparatus which is readily operated from any convenient source of pressure fluid, which may be quickly reloaded upon depletion of the material to be dispensed, and by which materials of heavy or semisolid character may be easily dispensed.

The invention is disclosed herein in connection with a particular construction and arrangement of the parts, which is intended by Way of example only, and it is to be understood that the apparatus is capable of modification within the spirit of the invention and the scope of the appended claims.

Having thus clearly shown and described the invention, what is claimed as new and desired to secure by Letters Patent, is:

1. In apparatus for dispensing fluent material under pressure; a pressure barrel, means forming an actuating chamber and a valve chamber in the barrel, a supply cylinder for fluent material, means connecting the barrel and cylinder together at one end and formed with a discharge bore in communication with said one end of the cylinder, a plunger slidably extended into said bore for movement in one direction to close the bore against the inflow of material from the cylinder and to apply pressure to material in the bore and in the other direction to open the bore to such flow, a supply piston movably disposed in said cylinder, an actuating piston in the actuating cham ber, passageway forming means connected to said actuating piston and slidably extended into said valve chamber and forming separate passageways in communication with the valve chamber and opening into said actuating chamber on opposite sides of said actuating piston, valve means in said valve chamber including a member movable to one position for coaction with said passageways in response to movement of the actuating piston in one direction to supply fluid from said valve chamber to said actuating chamber on one side of said actuating piston and toanother position in response to movement of the actuating piston in the other direction for such coaction to supply fluid from the valve chamber to the actuating chamber on the other side of the actuating piston, means positioned for coaction with said valve member to allow an outflow of fluid through each of said passageways during the flow of fluid into the actuating chamber through the other of said passageways and means for supplying fluid from a source of fluid under pressure to said valve chamber.

2. The apparatus as claimed in claim 1 including yield- .able means positioned for coaction with the barrel and valve member to yieldingly urge the valve member toward said one position in response to movement of the actuating piston in said other direction and toward said other position in response to movement of said actuating piston in said one direction.

3. The apparatus as claimed in claim 2 including means positioned for coaction with the barrel and valve means to hold the valve means against movement from one to another of said positions during movement of the actuating piston in either direction.

4, The apparatus as claimed in claim 1, wherein said valve means includes a valve block having a port for each of said passageways and said means for allowing outflow through said passageway includes an outlet in said block and said valve member is rotatably mounted on said block and shaped for coaction with the block upon movement of the member to said one position to open one of said ports to the interior of the valve chamber and to connect the other of said ports in communication with said outlet and upon movement of the valve member to said other position to open the other of said ports to the interior of the valve chamber and connect said one of said ports in communication with said outlet.

5. The apparatus as claimed in claim 1 including means positioned for coaction with the barrel, valve means and valve member to cause the member to move from one of said positions to the other with a snapping action when the actuating piston reaches a predetermined position of movement in either direction.

6. The apparatus as claimed in claim 2 including releasable means positioned for coaction with the valve means and member to hold the member against movement from either of said positions to the other during a predetermined movement of the actuating piston in either direction and means positioned for coaction with said barrel and releasable means to release the member when said actuating piston reaches a predetermined position of its movement in either direction.

References Cited by the Examiner UNITED STATES PATENTS 2,007,707 7/ 1935 Dodge 222-262 2,114,507 4/1938 Smith 222-262 2,610,768 9/1952 Le Clair 222-262 X SAMUEL F. COLEMAN, Primary Examiner. 

1. IN APPARATUS FOR DISPENSING FLUENT MATERIAL UNDER PRESSURE; A PRESSURE BARREL, MEANS FORMING AN ACTUATING CHAMBER AND A VALVE CHAMBER IN THE BARREL, A SUPPLY CYLINDER FOR FLUENT MATERIAL, MEANS CONNECTING THE BARREL AND CYLINDER TOGETHER AT ONE END AND FORMED WITH A DISCHARGE BORE IN COMMUNICATION WITH SAID ONE END OF THE CYLINDER, A PLUNGER SLIDABLY EXTENDED INTO SAID BORE FOR MOVEMENT IN ONE DIRECTION TO CLOSE THE BORE AGAINST THE INFLOW OF MATERIAL FROM THE CYLINDER AND TO APPLY PRESSURE TO MATERIAL IN THE BORE AND IN THE OTHER DIRECTION TO OPEN THE BORE TO SUCH FLOW, A SUPPLY PISTON MOVABLY DISPOSED IN SAID CYLINDER, AN ACTUATING PISTON IN THE ACTUATING CHAMBER, PASSAGEWAY FORMING MEANS CONNECTED TO SAID ACTUATING PISTON AND SLIDABLY EXTENDED INTO SAID VALVE CHAMBER AND FORMING SEPARATE PASSAGEWAYS IN COMMUNICATION WITH THE VALVE CHAMBER AND OPENING INTO SAID ACTUATING CHAMBER ON OPPOSITE SIDES OF SAID ACTUATING PISTON, VALVE MEANS IN SAID VALVE CHAMBER INCLUDING A MEMBER MOVABLE TO ONE POSITION FOR COACTION WITH SAID PASSAGEWAYS IN RESPONSE TO MOVEMENT OF THE ACTUATING PISTON IN ONE DIRECTION TO SUPPLY FLUID FROM SAID VALVE CHAMBER TO SAID ACTUATING CHAMBER ON ONE SIDE OF SAID ACTUATING PISTON AND TO ANOTHER POSITION IN RESPONSE TO MOVEMENT OF THE ACTUATING PISTON IN THE OTHER DIRECTION FOR SUCH COACTION TO SUPPLY FLUID FROM THE VALVE CHAMBER TO THE ACTUATING CHAMBER ON THE OTHER SIDE OF THE ACTUATING PISTON, MEANS POSITIONED FOR COACTION WITH SAID VALVE MEMBER TO ALLOW AN OUTFLOW OF FLUID THROUGH EACH OF SAID PASSAGEWAYS DURING THE FLOW OF FLUID INTO THE ACTUATING CHAMBER THROUGH THE OTHER OF SAID PASSAGEWAYS AND MEANS FOR SUPPLYING FLUID FROM A SOURCE OF FLUID UNDER PRESSURE TO SAID VALVE CHAMBER. 